private void GenerateNodes()
{
for (int i = 0; i < GridHeight; i++)
{
for (int j = 0; j < GridWidth; j++)
{
_grid[i, j] = new NodeHeap(false,
new Vector3((-_gridSize.x / 2) + _halfNodeWidth + (i * NodeHeight),
_halfNodeWidth,
(-_gridSize.y / 2) + _halfNodeWidth + (j * NodeWidth)),
i,
j);
if (Physics.CheckSphere(_grid[i, j].m_vPosition,
_halfNodeWidth,
_obstacleMask))
{
_grid[i, j]._nodeType = NodeHeap.NodeType.blocked;
}
else
{
_grid[i, j]._nodeType = NodeHeap.NodeType.open;
}
}
}
}
public int GetDistance(NodeHeap nodeA, NodeHeap nodeB)
{
int distanceX = Mathf.Abs(nodeA.m_iGridX - nodeB.m_iGridX);
int distanceY = Mathf.Abs(nodeA.m_iGridY - nodeB.m_iGridY);
if (distanceX > distanceY)
{
return(14 * distanceY + 10 * (distanceX - distanceY));
}
return(14 * distanceX + 10 * (distanceY - distanceX));
}
public void AStarPathfind(NodeHeap _startNode, NodeHeap _targetNode)
{
Stopwatch stopWatch = new Stopwatch();
stopWatch.Start();
Heap <NodeHeap> openHeap = new Heap <NodeHeap>((int)_pathGridManager._gridSize.x * (int)_pathGridManager._gridSize.y),
closedHeap = new Heap <NodeHeap>((int)_pathGridManager._gridSize.x * (int)_pathGridManager._gridSize.y);
openHeap.Add(_startNode);
while (openHeap.Count > 0)
{
NodeHeap currentNode = openHeap.RemoveFirst();
closedHeap.Add(currentNode);
if (currentNode == _targetNode)
{
RetracePath(_startNode, _targetNode);
stopWatch.Stop();
print("AStarPathFind() completed in " + stopWatch.ElapsedMilliseconds + " milliseconds.");
return;
}
foreach (NodeHeap neighbour in currentNode._nodeNeighbourList)
{
if (neighbour._nodeType == NodeHeap.NodeType.blocked || closedHeap.Contains(neighbour))
{
continue;
}
int movementCostToNeighbour = currentNode.m_iGCost + GetDistance(currentNode, neighbour);
if (movementCostToNeighbour < neighbour.m_iGCost ||
!openHeap.Contains(neighbour))
{
neighbour.m_iGCost = movementCostToNeighbour;
neighbour.m_iHCost = GetDistance(neighbour, _targetNode);
neighbour.m_Parent = currentNode;
}
if (!openHeap.Contains(neighbour))
{
openHeap.Add(neighbour);
openHeap.UpdateItem(neighbour);
}
}
}
}
private void RetracePath(NodeHeap start, NodeHeap end)
{
List <NodeHeap> path = new List <NodeHeap>();
NodeHeap current = end;
while (current != start)
{
path.Add(current);
current = current.m_Parent;
}
path.Reverse();
_pathGridManager._path = path;
}
private void DrawNodes()
{
NodeHeap playerGridCoordinates = GridLocator(_player.position);
NodeHeap targetGridCoordinates = GridLocator(_target.position);
for (int i = 0; i < GridHeight; i++)
{
for (int j = 0; j < GridWidth; j++)
{
if (_grid[i, j]._nodeType == NodeHeap.NodeType.open)
{
Gizmos.color = Color.clear;
}
if (_grid[i, j]._nodeType == NodeHeap.NodeType.blocked)
{
Gizmos.color = Color.red;
}
if (_grid[i, j].Equals(playerGridCoordinates))
{
Gizmos.color = Color.green;
}
if (_grid[i, j].Equals(targetGridCoordinates))
{
Gizmos.color = Color.magenta;
}
if (_path.Contains(_grid[i, j]))
{
Gizmos.color = Color.black;
}
Gizmos.DrawWireCube(_grid[i, j].m_vPosition,
new Vector3(NodeWidth, NodeHeight, NodeHeight));
}
}
}
private List <NodeHeap> ReturnNeighbours(PathGridManagerHeap pathGridManager, NodeHeap _currentNode)
{
List <NodeHeap> _neighbourList = new List <NodeHeap>();
for (int x = -1; x <= 1; x++)
{
for (int y = -1; y <= 1; y++)
{
if (x == 0 && y == 0)
{
continue;
}
if (_currentNode.m_iGridX + x >= 0 && // X cannot be negative.
_currentNode.m_iGridY + y >= 0 && // Y cannot be negative.
_currentNode.m_iGridX + x <= pathGridManager._gridSize.x - 1 && // X cannot be outside the grid's bounds.
_currentNode.m_iGridY + y <= pathGridManager._gridSize.y - 1) // Y cannot be outside the grid's bounds.
{
_neighbourList.Add(pathGridManager._grid[_currentNode.m_iGridX + x, _currentNode.m_iGridY + y]);
}
}
}
return(_neighbourList);
}
